DUBAI (Reuters) - A leading Bahraini human rights activist was denied bail on Tuesday on charges of spreading false news, a pro-opposition rights group reported.

The Bahrain Institute for Rights and Democracy added that Nabeel Rajab’s health is deteriorating after he underwent an operation last month for bleeding ulcers.

“Rajab is charged with ‘spreading false news’ and faces three years for telling news outlets that journalists and NGOs are barred from entering Bahrain,” the group said.

There was no immediate government comment on the report.

Rajab was a leading figure in a 2011 pro-democracy uprising led by Bahrain’s Shi’ite Muslim majority and he has been repeatedly detained.

An outspoken critic of the government, Rajab faces two other trials on charges of writing an editorial decrying prison conditions in the country and for tweets he is accused of making on human rights and Bahrain’s involvement in a war in Yemen.

In a New York Times column published under his byline in September, Rajab addressed readers in the first person, saying he was writing from a “Bahraini jail cell where I have been detained, largely in isolation, since the beginning of summer”.

The column said Bahrain was a country “that has subjected its people to imprisonment, torture and even death for daring to desire democracy”.

The United Nations Committee against Torture on Friday called on Bahrain to release Rajab from more than nine months of solitary confinement and investigate widespread allegations of ill-treatment and torture of detainees.

Bahrain denies any systematic abuse by police or in its prisons and says it is facing a violent uprising backed by its regional rival Iran.